gpio: pca953x driver handles pca9554 too

Teach drivers/gpio/pca953x.c about PCA9554, another compatible chip.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index 93f9167..7e40e8a 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -30,6 +30,7 @@
 	{ "pca9537", 4, },
 	{ "pca9538", 8, },
 	{ "pca9539", 16, },
+	{ "pca9554", 8, },
 	{ "pca9555", 16, },
 	{ "pca9557", 8, },
 	/* REVISIT several pca955x parts should work here too */